Overview: The Arizona Cardinals are looking to stay unbeaten as the team travels to St. Louis for a NFC West rivalry game against the Rams. It is the first time in nearly four decades that the Cardinals have started a season 4-0 and they are doing so by riding their championship caliber defense. The Rams have lived in the basement of the NFC for quite some time, but Jeff Fisher has the team going in the right direction in his first year at the helm. The Rams have a chance Thursday night to climb over the .500 mark for the first time since 2006.

What to watch on offense: The Cardinals offense has been far from spectacular. The unit has yet to go for more than 300 yards in any game this season and has been plagued with injuries. John Skelton continues to be sidelined with an ankle injury and starting running back Chris “Beanie” Wells was put on the IR before Week 4.

Look for Ryan Williams to have his first big day as a pro against the Rams. Williams has rushed 44 times for only 131 yards this season, but the Rams run defense has not been good this year. Their 135 yards allowed per game ranks 26th in the NFL.

In the passing game, look for Andre Roberts to continue his breakout year, as Larry Fitzgerald will draw most of the attention of the Rams’ 11th ranked pass defense. Roberts’ four receiving touchdowns have him No. 1 among receivers in the NFL.

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What to watch on defense: The Cardinals defense has carried the team to a perfect record. While the Cards are allowing 357 yards of offense per game, they have been able to keep opponents off the scoreboard. The teams 15.2 point per game allowed is third best in the NFL.

Look for veteran safety Adrian Wilson to have a big game. Wilson has more sacks (7.5) and interceptions (6) against the Rams than against any other NFL team. The Cardinals will continue to bring pressure from the linebacker spot with Sam Acho and Daryl Washington, so cornerbacks Patrick Peterson and William Gay should have a field day against struggling, third-year quarterback Sam Bradford.

Key Stats

- Kevin Kolb has a 120.2 quarterback rating on third down this season (19 of 28, 174 yards, 3 TDs, 0 INT).

- The Cardinals have only allowed four touchdowns this season, the lowest total in the NFL.

- 16 out of the last 20 games for the Cardinals have been decided by seven points or less.

Prediction: Cardinals win 21-10

The Cardinals defense overwhelms the lowly Rams offense and Ryan Williams will have his coming out party as a pro.